The present invention relates generally to pyrotechnic display devices commonly referred to as fireworks, and in particular, to a pyrotechnic display device configured to produce an aerial shell, comet, or mine which, when ignited, smokelessly expels either non-burning body containing a burst charge and stars, or a solid pyrotechnic color or effect, to generate a reduced smoke aerial display, comet display, or star display.
Traditionally, black power is used in the majority of pyrotechnic display devices for igniting and propelling solid pyrotechnic compositions such as star or comet displays from a launch tube. Black powder offer the advantages of rapid and hot combustion, thereby propelling the solid pyrotechnic compositions from the launch tubes to a desired apex while simultaneously providing sufficient heat to ignite the composition, a prime explosive, or a delay fuse on an aerial shell.
It is known however, that black powder propellant produces a large volume of smoke during combustion. This is particularly troublesome for pyrotechnic display devices intended for use within a building interior, such as an enclosed arena or stadium, or for use outside if the pyrotechnic display devices or aerial shells are discharged in close proximity to spectators, exhibitors, or other activities which would be obscured or impeded by the significant smoke produced during combustion.
A smokeless propellant which is commonly utilized in firearms is to provide an expelling force for a projectile is nitrocellulose. However, the use of nitrocellulose in entertainment pyrotechnic display devices is not common because nitrocellulose combustion occurs at a relatively low temperature. Low temperature combustion of nitrocellulose provides sufficient force to propel solid pyrotechnic compositions from a launch tube to a desired apex, but lacks a sufficient heat of combustion to ignite the compositions, their primes, or the delay fuses on aerial shells. Traditionally, nitrocellulose use in display pyrotechnic devices is limited to expelling non-burning items such as confetti, or it is utilized as a noise maker in party poppers and novelty devices.
Accordingly, there is a need in the industry for a display pyrotechnic device which is capable of both igniting solid pyrotechnic compositions, their primes, or aerial delay fuses and propelling the burning composition or aerial shell on a desired arc from a launch tube with a minimum amount of smoke.